A Case of Autoimmune Pancreatitis Manifested by a Pseudocyst and IgG4-Associated Cholangitis.

Department of Internal Medicine, Kyungpook National University Hospital, Daegu, Korea.

Abstract

Autoimmune pancreatitis (AIP) is a benign disorder and a unique form of chronic pancreatitis with several characteristic features. A cystic formation that mimics a pseudocyst is a rare finding. There have been a few reports of AIP complicated by pancreatic cysts. We present a case of AIP with multiple pseudocysts and obstructive jaundice caused by IgG4-associated cholangitis. We initially missed the diagnosis due to the pseudocyst. Based on the computed tomography images, laboratory findings and the therapeutic response to steroids, the case was diagnosed as AIP with pseudocysts and associated cholangiopathy.

The computed tomography findings on the first visit of the patient to our hospital in May 2008. There is a diffuse enlargement of the pancreas with multiple pseudocysts without parenchymal calcification.

Computed tomography (CT) (A) and endoscopic retrograde cholangiopancreatography (ERCP) (B) findings at the time of admission for the evaluation of jaundice in July 2008. CT shows diffuse intra-hepatic duct dilatation, focal luminal wall thickening and a narrowing lesion at the proximal common bile duct (CBD). ERCP demonstrates the stenosis of the proximal CBD with upstream dilation.

The computed tomography (CT) and endoscopic retrograde cholangiopancreatography (ERCP) findings after corticosteroid treatment for 3 months. (A) CT reveals an improvement in parenchymal swelling and the size and numbers of pseudocysts. (B) ERCP shows a complete resolution of the luminal narrowing and stricture of the proximal common bile duct.